Systems and methods for monitoring a wireless motor drive control system for handheld knives

ABSTRACT

A power pack for a power tool. The power pack includes an electric motor configured for driving engagement with the power tool. The power pack also includes a motor controller having a relay circuit connected a electric motor. The relay circuit includes has a switch selectively connected to a power supply. The power supply powers the electric motor. The motor controller also includes non-transitory computer-readable storage media having computer-executable instructions for monitoring operation of the stored power pack. When executed by at least one processor, the computer-executable instructions cause the at least one processor to: monitor input data relating to operation of the power pack; determine, based on the input data, that operation of the power pack deviated from an ideal state; and, based on the determination of deviation, cause the switch to electrically disconnect the electric motor from the power supply.

RELATED APPLICATIONS

This patent application claims priority to U.S. Patent Application Ser.No. 63/116,957, entitled WIRELESS MOTOR DRIVE CONTROL SYSTEM FORHANDHELD KNIVES, filed Nov. 23, 2020, the entire contents of which ishereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to powered knives, such as thosecommonly used in slaughterhouses for meat processing. More specifically,the present invention concerns braking and control components of poweredrotary knives.

BACKGROUND

Existing powered rotary knives are often used in the meat processingindustry for dressing an animal carcass. The process of dressing acarcass normally involves the removal of meat and fat from, as well ascutting, bones. Powered rotary knives enable workers to perform thisprocess with great efficiency.

However, existing powered rotary knives can be hazardous to operate andcontrol. For example, existing drive control(s) are rudimentary and canlead to unsafe operating conditions. For another example, existingpowered rotary knives are often exposed to unnecessary wear and tear dueto design flaws, which may render them unsafe or prone to prematurefailure.

This background discussion is intended to provide information related tothe present invention which is not necessarily prior art.

BRIEF SUMMARY

The following brief summary is provided to indicate the nature of thesubject matter disclosed herein. While certain aspects of the presentinvention are described below, the summary is not intended to limit thescope of the present invention.

A first aspect of the present invention concerns a power pack for apower tool. The power pack includes an electric motor configured fordriving engagement with the power tool. The power pack also includes amotor controller having a relay circuit in electrical communication withthe electric motor. The relay circuit includes a switch selectivelyelectrically connectable to a power supply. Electrical connection of theelectric motor to the power supply powers the electric motor. The motorcontroller also includes non-transitory computer-readable storage mediahaving computer-executable instructions for monitoring operation of thestored power pack. When executed by at least one processor, thecomputer-executable instructions cause the least one processor to:monitor input data relating to operation of the power pack; determine,based at least in part on the input data, that operation of the powerpack deviated from an ideal state; and, based on the determination ofdeviation, cause the switch to electrically disconnect the electricmotor from the power supply.

A second aspect of the present invention concerns a system forselectively powering a power tool. The system includes a power pack witha motor controller and an electric motor configured for drivingengagement with the power tool. The motor controller is in electricalcommunication with the electric motor and includes at least oneprocessor and non-transitory computer-readable storage media havingcomputer-executable instructions for monitoring operation of theelectric motor. When executed by the at least one processor, thecomputer-executable instructions cause the at least one processor to:monitor input data relating to operation of the electric motor;determine, based at least in part on the input data, that operation ofthe electric motor deviated from an ideal state; and, based on thedetermination of deviation, electrically disconnect the electric motorfrom the power supply.

Advantages of these and other embodiments will become more apparent tothose skilled in the art from the following description of the exemplaryembodiments which have been shown and described by way of illustration.As will be realized, the present embodiments described herein may becapable of other and different embodiments, and their details arecapable of modification in various respects. Accordingly, the drawingsand description are to be regarded as illustrative in nature and not asrestrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The Figures described below depict various aspects of systems andmethods disclosed therein. It should be understood that each Figuredepicts an embodiment of a particular aspect of the disclosed systemsand methods, and that each of the Figures is intended to accord with apossible embodiment thereof. Further, wherever possible, the followingdescription refers to the reference numerals included in the followingFigures, in which features depicted in multiple Figures are designatedwith consistent reference numerals.

FIG. 1 illustrates, in schematic and block diagram form, components of apower pack, hanger bracket and flex-shaft according to an embodiment ofthe present invention;

FIG. 2 illustrates, in schematic and block diagram form, components of ahandpiece according to an embodiment of the present invention and asecond end of the flex-shaft of FIG. 1, the handpiece being engaged withand driven by the power pack of FIG. 1;

FIG. 3 illustrates, in schematic and block diagram form, signal andelectrical flows across wired and wireless connections betweencomponents of the power pack and handpiece respectively of FIGS. 1 and2;

FIG. 4 illustrates, in block diagram form, components of the motorcontroller of FIGS. 1 and 3;

FIG. 5 illustrates, in schematic and block diagram form, circuit layoutsfor components of the power pack and handpiece respectively of FIGS. 1and 2 according to an embodiment of the present invention;

FIG. 6 is a flowchart illustrating at least a portion of the steps forcontrolling a handpiece in accordance with embodiments of the presentinvention; and

FIG. 7 is a flowchart illustrating at least a portion of the steps formonitoring one or more inputs reflecting system operation in accordancewith embodiments of the present invention.

The Figures depict exemplary embodiments for purposes of illustrationonly. One skilled in the art will readily recognize from the followingdiscussion that alternative embodiments of the systems and methodsillustrated herein may be employed without departing from the principlesof the invention described herein.

DETAILED DESCRIPTION

Turning first to FIG. 1, components of an exemplary power pack 10 areillustrated that include a motor 12, a power supply 14, a motorcontroller 16 and a housing 18. The motor 12 may comprise a directcurrent (DC) motor powered by, for example, a twenty-four volt (24V)power supply 14. The motor 12 may also include a connection to a groundcircuit. In an embodiment, the power supply 14 receives line power(e.g., in one hundred and twenty (120) or two hundred and forty (240)volt alternating current (AC)) and converts the line power totwenty-four volt (24V) power for supply to the motor 12. The line powermay also be used to power one or more of the electronic components ofthe power pack 10 and/or of a handpiece 38 discussed in more detailbelow. One of ordinary skill will appreciate, as noted above, that avariety of AC and DC motors (including brushless motors), operating witha variety of power supplies, are within the scope of the presentinvention.

The motor controller 16 may include and/or be in electroniccommunication with a radio frequency identification (RFID) reader 20.The RFID reader 20 may be housed within the same power pack housing 18as the motor 12, power supply 14 and/or motor controller 16. The RFIDreader 20 may also be positioned outside of and/or attached to thehousing 18. The RFID reader 20 may be compatible with one or more of lowfrequency, high frequency and/or ultra-high frequency tags, and mayoperate according to passive and/or active classification protocols andcomponents, without departing from the spirit of the present invention.

The power pack 10 may also include a cradle 22 configured to engage andsupport a portion of the handpiece 38 (see discussion below) when not inoperation. For example, the shape of the cradle 22 may be complementaryto contours of one or more portions of the handpiece 38, and may bedesigned to catch and support such complementary contours (e.g., bypresenting a space narrower than a rotary knife housing 55, and largerthan a handle 52, of the handpiece 38 into which the handle 52 may beinserted). Similarly, the power pack 10 may include a hanger bracket 24attached to the housing 18 and configured to engage with and besupported by a suitable support structure (e.g., by a hook embedded in anearby wall or a tower or stand for bearing the power pack 10).

One of ordinary skill will appreciate that a cradle 22 and/or hangerbracket 24 may be omitted or alternatively configured without departingfrom the scope of the present invention.

The power pack 10 may also include a flex-shaft quick connect 26. Anoutput shaft or other output component for transferring power generatedby the motor 12 may be made available for coupling at the quick connect26. In one or more embodiments, the output of the motor 12 istransferred to the handpiece 38 via a cable or flex-shaft 28 releasablycoupled to the quick connect 26.

The power pack may also include an ON button 30, an OFF button 32, and awireless pairing button 34. The ON and OFF buttons 22, 32 may comprisepush button switches or the like that, respectively, complete or breakone or more electrical circuits providing electricity from the linepower to the power pack components described herein (e.g., the motor 12,the power supply 14, the motor controller 16, and the RFID reader 20).One of ordinary skill will appreciate that a single button and/or switchmay be utilized in lieu of separate ON and OFF buttons without departingfrom the spirit of the present invention.

Further, the wireless pairing button 34 may also comprise a switch that,when actuated, provides a signal to the controller 16 for initiatingwireless pairing operations described in more detail below.

It is foreseen that the switches of one or more of the ON button 30, OFFbutton 32 and wireless pairing button 34 may be alternativelyrepresented as a digital interface for receiving user input, such as atouchscreen display, without departing from the spirit of the presentinvention.

Turning now to FIG. 2, the handpiece 38 may receive mechanical powertransferred from the power pack 10 via the flex-shaft 28. The handpiece38 may also include a wireless transceiver 40 configured to transmitwireless signals triggered by a magnetic switch 42, substantially asdescribed above. The handpiece 38 may also include a battery 44 forpowering the electronic components of the handpiece 38. The battery 44may be rechargeable and may include and/or be in electroniccommunication with a port for receiving a universal serial bus (USB)connector 58 or plug for charging (see FIG. 5). In one or moreembodiments, the wireless transceiver 40 may be configured to receivepower from a wired or wireless power source other than the battery 44 ifthe battery voltage diminishes below a threshold for providing power tothe handpiece. For example, the wireless transceiver may switch thepower source from the battery 44 to the USB connector 58 upon connectinga power source to the USB connector 58.

The handpiece 38 may also include an RFID tag 46 for use in wirelesspairing and related procedures discussed in more detail below. Moregenerally, the handpiece 38 also includes a trigger 48 (including amagnet for actuating the switch 42 whenever the trigger 48 is depresseda threshold degree) and a power tool 51 comprising a high-speed knifeincluding a handle 52, a rotary knife 54 and rotary knife housing 55(see discussion above). The power tool 51 may include or comprisecomponents of a power tool according to embodiments of the presentinvention that substantially conform to those corresponding componentsof a rotary knife described in U.S. Pat. No. 10,889,018, issued on Jan.12, 2021, and entitled ROTARY KNIFE BLADE WITH DOUBLE BEVELED INSIDESURFACE, the entire contents of which is hereby incorporated herein byreference. One of ordinary skill will appreciate, however, that varioushandpiece constructions are within the scope of the present invention.

Generally, it should be noted that the RFID components 20, 46 maycommunicate between one another using radio waves whereby digital dataencoded in the RFID tag 46 may be captured by the RFID reader 20. TheRFID reader 20 may capture digital data encoded in the RFID tag 46 whentriggered by an electromagnetic interrogation pulse from the nearby RFIDreader 20. In one or more embodiments, the wireless transceiver 40 mayreceive additional data (e.g., relating to configuration for furthercommunications, encryption key data, or the like) from the wirelesstransceiver 48 after completion of a pairing process described in moredetail below.

Turning now to FIGS. 3-5, a variety of logical components of the powerpack 10 and handpiece 38 are illustrated. Initially, it should be notedthat the controller 16 may include a processing element 70, a memoryelement 72 and a communication element 74. The communication element 74generally allows communication with other systems or devices, such asthe handpiece 38, e.g., via wireless communication and/or datatransmission over one or more direct or indirect radio links betweendevices. The communication element 74 may include signal or datatransmitting and receiving circuits, such as antennas, amplifiers,filters, mixers, oscillators, digital signal processors (DSPs), and thelike. The communication element 74 may establish communicationwirelessly by utilizing RF signals and/or data that comply withcommunication standards such as cellular 2G, 3G, or 4G, WiFi, WiMAX,Bluetooth™, and the like, or combinations thereof. In addition, thecommunication element 74 may utilize communication standards such asANT, ANT+, Bluetooth™ low energy (BLE), the industrial, scientific, andmedical (ISM) band at 2.4 gigahertz (GHz), or the like.

In one or more particular embodiments, the wireless transceiver 48and/or the RFID reader 20 may comprise or be integral with thecommunication element 74. Further, in one or more embodiments, thewireless transceivers 40, 48 and/or communication element 74 mayindividually or collectively include a software application fordescribing, executing, and enabling wireless communications, such asthose transmitted in accordance with standards put forth by theBluetooth Special Interest Group (SIG) under the mark BLUETOOTH™ as ofthe initial filing of the present application. One of ordinary skillwill appreciate that pairing and wireless communication may be achievedaccording to other wireless communication standards and technologieswithout departing from the spirit of the present invention. In one ormore embodiments, the wireless transceivers 40, 48 and communicationelements 74 may use signals corresponding to one or more such wirelessstandard(s) to process, route, connect, establish, disconnect, or searchfor wireless signals between one or more devices, including to performthe operations described in more detail below.

The memory element 72 of the controller 16 may include non-volatileand/or non-transitory electronic hardware data storage components suchas read-only memory (ROM), programmable ROM, erasable programmable ROM,random-access memory (RAM) such as static RAM (SRAM) or dynamic RAM(DRAM), cache memory, hard disks, floppy disks, optical disks, flashmemory, thumb drives, universal serial bus (USB) drives, or the like, orcombinations thereof. The memory element 72 may include, or mayconstitute, a “computer-readable medium.” The memory element 72 maystore the instructions, code, code segments, software, firmware,programs, applications, apps, modules, agents, services, daemons, or thelike that are executed by the processing element 70, including a programconfigured to perform wireless pairing with the motor-control wirelesstransceiver 48, dynamic braking with a braking resistor 50, watchdog 52operations, and other steps outlined herein. The memory element 72 mayalso store items described throughout this disclosure, such asoperational parameters and readings outlined herein. In the illustratedembodiment, the memory element 72 comprises electrically erasableprogrammable read-only memory (EEPROM) 53.

The processing element 70 of the controller 16 may include electronichardware components such as processors. The processing element 70 mayinclude digital processing unit(s). The processing element 70 mayinclude microprocessor(s) (single-core and multi-core),microcontrollers, digital signal processors (DSPs), field-programmablegate arrays (FPGAs), analog and/or digital application-specificintegrated circuits (ASICs), or the like, or combinations thereof. Theprocessing element 70 may generally execute, process, or runinstructions, code, code segments, software, firmware, programs,applications, apps, modules, agents, processes, services, daemons, orthe like, including the program configured to perform the wirelesspairing, dynamic braking and watchdog operations outlined herein. Theprocessing element 70 may also include hardware components such asfinite-state machines, sequential and combinational logic, and otherelectronic circuits that can perform the functions necessary for theoperation of the current invention. The processing element may be incommunication with the other electronic components through serial orparallel links that include address busses, data busses, control lines,and the like. Through hardware, software, firmware, or combinationsthereof, the processing element 70 may be configured or programmed toperform operations described elsewhere herein.

Other components of the exemplary controller 16 illustrated in FIG. 3include a braking resistor 50, a relay 54, and a driver/half-bridge 56.The driver/half-bridge 56 receives converted twenty-four volt (24V)power and responds to input from the controller 16 to vary (and managethe polarity of) electrical feed to the motor 12 according to controlalgorithm(s). For example, the controller 16 may be configured to varyoutput from the electric motor 12 based at least in part on a user'sinput. In one or more embodiments, the output may vary in response to,for example, the strength of signal generated by the magnetic switch 42(i.e., the user's input) which, in turn, may depend on the proximity ofthe trigger 48 (i.e., on how much the user depresses the trigger 48).Moreover, in one or more embodiments, the controller 16 may beconfigured to match the motor back electromotive force (EMF) to thecontroller output ramp to avoid initial dynamic braking and minimizestress on the controller 16. The controller 16 and/or driver/half-bridge56 may implement pulse width modulation (PWM) for powering the motor 12.It should be noted that a variety of motor control strategies may beimplemented without departing from the spirit of the present invention.

The relay 54 includes a switch responsive to input from the watchdog 52component or logic of the controller 16. The watchdog 52, discussed inmore detail below, at least in part determines whether the relay 54 isto remain open or closed (thereby, respectively, cutting off orpermitting the flow of power from the driver/half-bridge 56 to the motor12).

The braking resistor 50 comprises a power resistor used in dynamicbraking of the motor 12. The braking resistor 50 may be configured suchthat the motor 12 is slowed at variable rates depending on theresistance of the braking resistor 50. More particularly, when the motor12 is to be slowed down or stopped, kinetic energy of the motor may betransformed into electrical energy which may be dissipated as heat usingthe (preferably rheostatic) braking resistor 50.

Further, it should be noted that the control functions carried out bythe controller 16 may be implemented via a wide variety of electroniccomponents without departing from the spirit of the present invention.

Moreover, referring to FIG. 1, the RFID reader 20 is illustrated asbeing positioned in proximity to or integral with the cradle 22, suchthat the operational range of the RFID reader 20 encompasses the cradle22 and/or that portion of the cradle 22 that is configured to receivethe handpiece 38. In this manner, bringing the RFID tag 46 proximate toor into contact with the cradle 22 also brings the RFID tag 46 near theRFID reader 20, enabling pairing operations described in more detailbelow.

One of ordinary skill will appreciate that the RFID tag 46 may bepositioned inside the rotary knife housing 56 without departing from thespirit of the present invention. Moreover, the rotary knife housing 56may be constructed to provide partial or complete protection from andisolation against ingress of water and/or environmental contaminants.

In addition, it should be noted that the preferred embodiment includesseveral status indicator lights embedded respectively in the powerpackhousing 18 and housing of the handpiece 38 (e.g., wireless status LED60, wireless status LED 61, motor status LED 62, battery status LED 64or the like).

The system may include additional, less, or alternate apparatuses orcomponents, including those discussed elsewhere herein and/or in theother Figures attached hereto.

Exemplary Method for Wireless Control of Powered Hand Tool

FIG. 6 depicts a block flow diagram associated with exemplarycomputer-implemented methods for pairing, using and wirelesslycontrolling handpiece power tools. Some steps may be performedconcurrently as opposed to sequentially and may in some cases beperformed in a different order. In addition, some steps may be optional.The computer-implemented method(s) are described below, for ease ofreference, as being executed by exemplary devices and componentsintroduced with the embodiments illustrated in FIGS. 1-5. For example,the steps of the computer-implemented method(s) may be performed by thepower pack and handpiece illustrated therein and described above, atleast in part through the utilization of processors, transceivers,hardware, software, firmware, or combinations thereof. In one or moreembodiments, the steps set out below for a single handpiece and powerpack are substantially repeated in connection with pairing, using andwirelessly controlling a plurality of other powered handheld kniveswithin the same general vicinity or at the same premises. A personhaving ordinary skill will also appreciate that responsibility for allor some of such actions may be distributed differently among suchdevices or other computing devices without departing from the spirit ofthe present invention.

One or more computer-readable medium(s) may also be provided. Thecomputer-readable medium(s) may include one or more executable programs,such as a controller program, stored thereon, wherein the program(s)instruct one or more processing elements to perform all or certain stepsoutlined herein. The program(s) stored on the computer-readablemedium(s) may instruct the processing element(s) to perform additional,fewer, or alternative actions, including those discussed elsewhereherein.

Referring to step 100, a user may place a handpiece comprising a poweredrotary knife on a cradle of a power pack. A motor controller may sensethe proximity of a wireless transceiver or RFID tag of the handpiece(e.g., via an RFID reader and/or a motor-control wireless transceiver,or by otherwise detecting that the handpiece has been placed on a cradleof the power pack), and the proximity may trigger or serve as aprecondition for wireless pairing processes. A pairing button of themotor controller may also or alternatively be pushed to trigger or serveas a precondition for pairing of the handpiece to the power pack, asdiscussed in more detail below. One of ordinary skill will appreciatethat a variety of wireless signals containing handpiece identificationdata may be used for pairing the new handpiece with the power pack. Thewireless pairing signals may be received by the motor-control wirelesstransceiver upon placing the new handpiece inside of the cradle on thepower pack.

Referring to step 102, the pairing button of the motor controller may bepressed. In the illustrated embodiment, the motor controller detects ordetermines whether the pairing button has been pushed. In an embodiment,such a determination may include determining whether the pairing buttonor switch is presently active or has been activated within apre-determined time period.

Referring to step 104, the pairing process may not proceed and/or may beterminated if the determination at step 102—relating to the motorcontroller deciding whether the pairing button has been pushed—is “No.”

Referring to step 106, if, alternatively, the determination at step 102is “Yes,” the motor controller may determine if one or more RFID tag(s)is/are read. In one or more embodiments, the motor controller activatesthe RFID reader to receive signals from the RFID tag(s) in connectionwith making the determination at step 106.

Referring to step 108, if no RFID tag signal is read/detected at step106, or the pairing process is otherwise terminated for failure tosatisfy a condition thereof, the motor controller or its capacity forinitiating supply of power to the motor may be disabled. Moreover,referring to step 110, in such cases the motor controller may alsoconfirm that it is not wirelessly paired with an unknown handpiece(i.e., one for which an RFID tag signal does not match the RFID signalof a previously paired handpiece and/or for which a complete wirelesspairing process has not otherwise been completed) as a condition forresetting the motor controller for a future pairing process. Afterconfirming that the motor controller is not wirelessly paired with theunknown handpiece at step 110, the motor controller may cycle back toagain deciding if the pairing button has been pushed, at step 102.

Referring to step 112, if an RFID tag signal is read/detected at step106, the motor controller may proceed by pairing with the correspondinghandpiece. In one or more embodiments, the pairing process may includewriting unique information regarding the handpiece to memory (e.g., tothe EEPROM of the motor controller). For example, the RFID reader mayadhere to near field communication (NFC) protocols, and the handpieceRFID tag signal may include credentials or unique identifyinginformation for the handpiece and/or wireless transceiver embedded inthe handpiece. In this manner, the RFID signal may uniquely identify thehandpiece to the motor controller, and such unique identifyinginformation may be stored at the motor controller and/or utilized tocomplete wireless pairing between the handpiece and the motorcontroller.

In one or more embodiments, all, or some of the information in the RFIDtag signal may be used in security applications, for example inestablishing encryption keys or the like for securing wirelesscommunications between the handpiece and the motor controller.

In one or more embodiments, the pairing process may also includeestablishment of associated encryption protocols and keys for use insecure wireless communications between the handpiece and the motorcontroller. It should also be noted that the pairing of the handpiece tothe power pack is preferably persistent. In one or more embodiments, thepairing is retained in the memory element of the controller unless anduntil it is overwritten via a new pairing procedure (e.g., pairing to anew handpiece), and regardless of whether electronic components of thepower pack or handpiece and/or power to the motor are turned off.

One of ordinary skill will appreciate that, in one or more embodiments,the motor controller may first validate a single RFID tag signal againstone or more conditions before completing the pairing process. Moreover,one of ordinary skill will appreciate that receipt of multiple RFID tagsignals during the pairing process outlined above may prompt a user toselect one such RFID tag (or handpiece) for pairing and/or may result intermination of the pairing process.

If at least one handpiece has been properly identified to the motorcontroller via an RFID tag signal, the motor controller may completesecure wireless pairing with the handpiece in connection with step 112.

Referring to step 124, the motor controller may determine whether it isreceiving a paired wireless signal from the handpiece wirelesstransceiver. In one or more embodiments, such a signal is receivedwhenever a magnetic switch at the handpiece is activated by, forexample, squeezing a magnet-containing trigger of the paired handpieceas discussed in more detail above.

Referring to step 126, in one or more embodiments, the motor controlleris in an “ON” state and a sequence for using the paired handpieceincludes activating or turning “ON” a power supply, as portrayed in step128. Referring also to step 130, the power supply may provide power tothe motor controller. One skilled in the art will appreciate that inaddition to providing power to the motor controller, the power supplymay also power the motor controller differently, for example via AC linepower. One or more of steps 126, 128, 130 may serve as logical orphysical preconditions—in addition to confirmation of receipt of apaired wireless signal at step 124—required to be satisfied beforeproceeding to step 132, described in more detail below.

Referring to step 132, if the motor controller is receiving a pairedwireless signal from a handpiece, the motor controller may cause itsassociated electronic components (e.g., a driver/half-bridge and/orrelay circuit) to supply power from the power supply to the motor,causing the motor to be operational and/or in an “ON” and operatingstate. As noted above, in one or more embodiments, one or more of steps126, 128 and 130 may serve as additional logical or physicalpreconditions to be satisfied to reach step 132 and the “ON” state.Referring to step 134, a DC motor being in the “ON” state may result inrotation of a flex-shaft or other drivetrain component and consequentoperation of the handpiece (e.g., operation of a high-speed knife of thehandpiece).

Generally, it should be noted that a “DC motor ON” process in step 132may only be reached in embodiments of the present invention if a pairedwireless signal is being received concurrently (see step 124). As notedabove, in one or more embodiments, such a signal is received as a resultof activation of a magnetic switch on a handpiece by, for example,squeezing a proximate, corresponding trigger. The switch may comprise aHall effect sensor or another sensor configured to respond to and beactivated by a threshold degree of proximity of a magnet orferromagnetic element(s) of the trigger.

Referring to step 136, an “OFF” condition for the motor may be reachedif a “System OFF” input is received by the motor controller (e.g.,through activation of a corresponding switch/button by a user). Wheresuch input is received by the motor controller, the power supply may becorrespondingly turned off or retained in an off state at step 138.Referring to step 140, the power to the motor controller may likewise becut when the power supply is turned off or retained in an off state atstep 138.

Referring to step 142, if the motor controller is not receiving a pairedwireless signal from the handpiece, the associated electronic components(e.g., the driver/half-bridge and/or relay circuit) of the motorcontroller will not supply power to the motor, resulting in the motorbeing in an “OFF” condition.

One or more of steps 136, 138 and 140 may serve as additional oralternative logical or physical preconditions which, if satisfied, leadto or cause the “DC Motor Off” state of step 142.

Referring to step 144, in conditions where the motor controllerdetermines or physical conditions require that the motor should reduceoutput or be switched from operation into an “OFF” condition, dynamicbraking (e.g., via a braking resistor discussed in more detail above)may be used to slow the motor. For example, in connection with cuttingpower to the leads of a motor with a moving armature, the motorcontroller may close a relay circuit to complete a circuit for flow ofelectricity between the motor to a braking resistor and dissipation ofenergy by the braking resistor (e.g., as heat). It should be noted thata circuit loop may also be added between the braking resistor and themotor. Once the motor output halts, the handpiece will cease operation,as noted in step 146.

Turning now to FIG. 7, a motor controller of a power pack mayalternatively or additionally implement a watchdog failsafe mode oralgorithm in one or more embodiments for controlling operation of ahandpiece driven by the power pack. The watchdog algorithm may causecontinuous or intermittent monitoring of one or more inputs reflectingsystem operation in step 150, determine an ideal state for a relaycircuit of the motor controller that should result from the one or moreinputs at any given time in step 152, and determine whether the relaycircuit achieved or deviated from the ideal state(s) in step 154. Thewatchdog algorithm may also, based on the determination of deviation,cause the switch to electrically disconnect the electric motor from thepower supply in step 156. In one or more embodiments, the relay circuitstates are binary, i.e., the relay circuit is either normally open ornormally closed (i.e., motor “ON” or “OFF,” respectively), and the motorcontroller will determine whether the relay circuit is operating in theintended manner.

In one or more embodiments, the relay circuit is activated to a first orsecond state corresponding to the state of the electric motor. Forexample, the relay circuit may activate to the first state(corresponding to motor “ON”), in which the relay circuit mayelectrically connect the electric motor to the power supply. When theelectric motor is connected to the power supply, the relay circuit maybe open. In another example, the relay circuit may activate to thesecond state (corresponding to motor “OFF”), in which the relay circuitmay electrically disconnect the electric motor from the power supply (inwhich case, the relay circuit may instead electrically connect theelectric motor to the braking resistor). When the electric motordisconnects from the power supply, the relay circuit may be closed.

Referring again to step 154, the determination of deviation may includedetermining that portions of the input data generated by an electricalcomponent of the power pack are insufficient to establish normaloperation. For example, such input data may be insufficient due to asystem failure to communicate between one or more components. In anotherexample, such input data may be insufficient to establish normaloperation because the input data became corrupt during the transmissionof the input data between components.

In one or more embodiments, the watchdog algorithm may be implemented inconnection with the steps for wireless control described above and mayrepresent an integral or independent condition or set of conditionsleading to the DC Motor OFF step 142 described above.

Determining an ideal state for the relay circuit at any given moment intime may include analyzing the one or more inputs against one or moreconditions. For example, in one or more embodiments, the ideal state ofa relay circuit will not permit the motor to operate at one hundredpercent (100%) duty cycle.

For another example, control signals to a driver/half-bridge of thepower pack, and an output level of the driver/half-bridge, may bemonitored. The failsafe watchdog algorithm may determine at any giventime that the level of output is not close enough (i.e., within apre-determined threshold) to what should have resulted fromcorresponding control signal(s) recorded by the controller. Accordingly,the algorithm may determine an ideal state and deviation therefrom.Namely, the algorithm may determine that, at a given time or within agiven timeframe, the relay circuit did not achieve its ideal state(s)and should have been closed for failure of sufficient output from thedriver/half-bridge.

For still another example, receipt of paired wireless signals and thestatus of the relay circuit may be monitored. The failsafe watchdogalgorithm may determine at any given time that the relay circuit wasopen when corresponding wireless signals were not received, and/or thatthe relay circuit was closed when corresponding wireless signals werereceived. Accordingly, the algorithm may determine an ideal state anddeviation therefrom. Namely, the algorithm may determine that, at agiven time or within a given timeframe, the relay circuit did notachieve its ideal state(s) based on the paired wireless signals receivedby the motor controller.

Wherever the failsafe watchdog algorithm determines that the relaycircuit did not achieve one or more ideal state(s), it may direct thatpower to the motor be cut off or that the relay circuit be closed,and/or may otherwise cease operations of the motor and/or handpiece (seestep 156).

The ideal state may be a threshold for permitted deviation of the powersupply output (from the motor) level from a corresponding outputspecified in the control signals governing the power supply. It shouldbe noted that one or more ideal states(s) of the relay circuit may bebased at least in part by a pre-defined state. A pre-defined state maybe a set of conditions, operational data, identification information, orthe like relating to the relay circuit, or an ideal state previouslyused by the hand piece.

In addition, one or more ideal state(s) of the relay circuit may atleast in part comprise a variable ideal state. The variable ideal statemay change based at least in part on the gradual, normalwear-and-tear-related changes experienced by a handpiece over longusage, and the corresponding changes to expected values for measuredvariables over that time. Other factors that might lead to or inform avariable ideal state may include connection duration between the handpiece and the power pack and/or motor operation duration. In one or morepreferred embodiments of the invention, the relay circuit may beconfigured to transmit a signal indicative of a current relay state toat least one processor of the motor controller.

It should also be noted that one or more ideal state(s) may represent anideal range of values for one or more data types or relationshipsbetween values of two or more data types. Data types may include powersupply output level, control signals to the power supply, indicators ofthe ideal state for the relay circuit, motor operation duration,timestamps pertaining to the use of one or more components, records ofpaired wireless communication signals, or associated ideal state(s). Oneskilled in the art will appreciate that additional data types orrelationships between data types may be used to determine one or moreideal state(s) without departing from the spirit of the invention.

The preferred forms of the invention described above are to be used asillustrations only and should not be utilized in a limiting sense ininterpreting the scope of the present invention. Obvious modificationsto the exemplary embodiments, as hereinabove set forth, could be readilymade by those skilled in the art without departing from the spirit ofthe present invention.

ADDITIONAL CONSIDERATIONS

In this description, references to “one embodiment”, “an embodiment”, or“embodiments” mean that the feature or features being referred to areincluded in at least one embodiment of the technology. Separatereferences to “one embodiment”, “an embodiment”, or “embodiments” inthis description do not necessarily refer to the same embodiment and arealso not mutually exclusive unless so stated and/or except as will bereadily apparent to those skilled in the art from the description. Forexample, a feature, structure, act, etc. described in one embodiment mayalso be included in other embodiments but is not necessarily included.Thus, the current technology can include a variety of combinationsand/or integrations of the embodiments described herein.

Throughout this specification, plural instances may implementcomponents, operations, or structures described as a single instance.Although individual operations of one or more methods are illustratedand described as separate operations, one or more of the individualoperations may be performed concurrently, and nothing requires that theoperations be performed in the order illustrated. Structures andfunctionality presented as separate components in example configurationsmay be implemented as a combined structure or component. Similarly,structures and functionality presented as a single component may beimplemented as separate components. These and other variations,modifications, additions, and improvements fall within the scope of thesubject matter herein.

Certain embodiments are described herein as including logic or a numberof routines, subroutines, applications, or instructions. These mayconstitute either software (e.g., code embodied on a machine-readablemedium or in a transmission signal) or hardware. In hardware, theroutines, etc., are tangible units capable of performing certainoperations and may be configured or arranged in a certain manner. Inexample embodiments, one or more computer systems (e.g., a standalone,client or server computer system) or one or more hardware modules of acomputer system (e.g., a processor or a group of processors) may beconfigured by software (e.g., an application or application portion) ascomputer hardware that operates to perform certain operations asdescribed herein.

In various embodiments, computer hardware, such as a processing element,may be implemented as special purpose or as general purpose. Forexample, the processing element may comprise dedicated circuitry orlogic that is permanently configured, such as an application-specificintegrated circuit (ASIC), or indefinitely configured, such as an FPGA,to perform certain operations. The processing element may also compriseprogrammable logic or circuitry (e.g., as encompassed within ageneral-purpose processor or other programmable processor) that istemporarily configured by software to perform certain operations. Itwill be appreciated that the decision to implement the processingelement as special purpose, in dedicated and permanently configuredcircuitry, or as general purpose (e.g., configured by software) may bedriven by cost and time considerations.

Accordingly, the term “processing element” or equivalents should beunderstood to encompass a tangible entity, be that an entity that isphysically constructed, permanently configured (e.g., hardwired), ortemporarily configured (e.g., programmed) to operate in a certain manneror to perform certain operations described herein. Consideringembodiments in which the processing element is temporarily configured(e.g., programmed), each of the processing elements need not beconfigured or instantiated at any one instance in time. For example,where the processing element comprises a general-purpose processorconfigured using software, the general-purpose processor may beconfigured as respective different processing elements at differenttimes. Software may accordingly configure the processing element toconstitute a particular hardware configuration at one instance of timeand to constitute a different hardware configuration at a differentinstance of time.

Computer hardware components, such as transceiver elements, memoryelements, processing elements, and the like, may provide information to,and receive information from, other computer hardware components.Accordingly, the described computer hardware components may be regardedas being communicatively coupled. Where multiple of such computerhardware components exist contemporaneously, communications may beachieved through signal transmission (e.g., over appropriate circuitsand buses) that connect the computer hardware components. In embodimentsin which multiple computer hardware components are configured orinstantiated at different times, communications between such computerhardware components may be achieved, for example, through the storageand retrieval of information in memory structures to which the multiplecomputer hardware components have access. For example, one computerhardware component may perform an operation and store the output of thatoperation in a memory device to which it is communicatively coupled. Afurther computer hardware component may then, at a later time, accessthe memory device to retrieve and process the stored output. Computerhardware components may also initiate communications with input oroutput devices, and may operate on a resource (e.g., a collection ofinformation).

The various operations of example methods described herein may beperformed, at least partially, by one or more processing elements thatare temporarily configured (e.g., by software) or permanently configuredto perform the relevant operations. Whether temporarily or permanentlyconfigured, such processing elements may constitute processingelement-implemented modules that operate to perform one or moreoperations or functions. The modules referred to herein may, in someexample embodiments, comprise processing element-implemented modules.

Similarly, the methods or routines described herein may be at leastpartially processing element-implemented. For example, at least some ofthe operations of a method may be performed by one or more processingelements or processing element-implemented hardware modules. Theperformance of certain of the operations may be distributed among theone or more processing elements, not only residing within a singlemachine, but deployed across a number of machines. In some exampleembodiments, the processing elements may be located in a single location(e.g., within a home environment, an office environment or as a serverfarm), while in other embodiments the processing elements may bedistributed across a number of locations.

Unless specifically stated otherwise, discussions herein using wordssuch as “processing,” “computing,” “calculating,” “determining,”“presenting,” “displaying,” or the like may refer to actions orprocesses of a machine (e.g., a computer with a processing element andother computer hardware components) that manipulates or transforms datarepresented as physical (e.g., electronic, magnetic, or optical)quantities within one or more memories (e.g., volatile memory,non-volatile memory, or a combination thereof), registers, or othermachine components that receive, store, transmit, or displayinformation.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

The patent claims at the end of this patent application are not intendedto be construed under 35 U.S.C. § 112(f) unless traditionalmeans-plus-function language is expressly recited, such as “means for”or “step for” language being explicitly recited in the claim(s).

Although the invention has been described with reference to theembodiments illustrated in the attached drawing figures, it is notedthat equivalents may be employed, and substitutions may be made hereinwithout departing from the scope of the invention as recited in theclaims.

Having thus described various embodiments of the invention, what isclaimed as new and desired to be protected by the inventor(s) includesthe following:

We claim:
 1. A power pack for a power tool, the power pack comprising: an electric motor configured for driving engagement with the power tool; a motor controller including a relay circuit in electrical communication with the electric motor, the relay circuit comprising a switch selectively electrically connectable to a power supply, whereby electrical connection of the electric motor to the power supply powers the electric motor; and non-transitory computer-readable storage media having computer-executable instructions for monitoring operation of the power pack stored thereon, wherein when executed by at least one processor the computer-executable instructions cause the at least one processor to— monitor input data relating to operation of the power pack, determine, based at least in part on the input data, that operation of the power pack deviated from an ideal state, based on the determination of deviation, cause the switch to electrically disconnect the electric motor from the power supply.
 2. The power pack of claim 1, said power supply being supplied via at least one of a driver and a half-bridge converter.
 3. The power pack of claim 1, said computer-executable instructions, when executed by the at least one processor, further causing the at least one processor to determine an ideal state of operation of the power pack.
 4. The power pack of claim 3, said ideal state defining, for one or more data types represented in the input data, at least one of the following: an ideal range of values for the one or more data types, and a relationship between values of two or more of the one or more data types.
 5. The power pack of claim 4, said one or more data types including power supply output level, control signals to the power supply, and indicators of the ideal state of the relay circuit, said ideal state including— a threshold for permitted deviation of the power supply output level from a corresponding output specified in the control signals to the power supply, pre-defined states of the relay circuit that correspond to operation within and outside of the threshold.
 6. The power pack of claim 5, said input data of the one or more data types including corresponding timestamps.
 7. The power pack of claim 4, said one or more data types including motor operation duration, said ideal state including— a pre-determined duty cycle for motor operation, pre-defined states of the relay circuit that respectively correspond to the motor operation duration being in compliance with and outside of the pre-determined duty cycle.
 8. The power pack of claim 4, said one or more data types including records of paired wireless communication signals received from the power tool, said ideal state including— pre-defined states of the relay circuit that respectively correspond to time periods in which the paired wireless communication signals are received and in which the paired wireless communication signals are not received.
 9. The power pack of claim 1, further comprising a braking resistor electrically connectable to the relay circuit, whereby electrical connection of the electric motor to the braking resistor permits electrical energy from the electric motor to be dissipated by the braking resistor at least partly in the form of heat.
 10. The power pack of claim 1, further comprising a housing, said relay circuit being co-located with the electric motor within said housing.
 11. A system for selectively powering a power tool, the system comprising: a power tool; and a power pack including a motor controller and an electric motor configured for driving engagement with the power tool; said motor controller in electrical communication with the electric motor and including at least one processor and non-transitory computer-readable storage media having computer-executable instructions for monitoring operation of the electric motor stored thereon, wherein when executed by the at least one processor the computer-executable instructions cause the at least one processor to— monitor input data relating to operation of the electric motor, determine, based at least in part on the input data, that operation of the electric motor deviated from an ideal state, based on the determination of deviation, electrically disconnect the electric motor from the power supply.
 12. The system of claim 11, said power tool comprising a rotary knife.
 13. The system of claim 11, said computer-readable instructions, when executed by the at least on processor, further causing the at least one processor to— receive a user input, vary an output of the electric motor based on the user input.
 14. The system of claim 11, wherein the input data is obtained through continuous or intermittent monitoring of one of more inputs reflecting system operations.
 15. The system of claim 11, wherein the power pack is in wireless communication with a transceiver of the power tool.
 16. The system of claim 11, said computer-executable instructions, when executed by the at least one processor, further causing the at least one processor to determine an ideal state of operation of the power pack.
 17. The system of claim 16, said ideal state defining, for one or more data types represented in the input data, at least one of the following: an ideal range of values for the one or more data types, and a relationship between values of two or more of the one or more data types.
 18. The system of claim 17, said one or more data types including power supply output level, control signals to the power supply, and indicators of the state of the relay circuit, said ideal state including— a threshold for permitted deviation of the power supply output level from a corresponding output specified in the control signals to the power supply, pre-defined states of the relay circuit that correspond to operation within and outside of the threshold.
 19. The system of claim 17, said one or more data types including motor operation duration, said ideal state including— a pre-determined duty cycle for motor operation, pre-defined states of the relay circuit that respectively correspond to the motor operation duration being in compliance with and outside of the pre-determined duty cycle.
 20. The system of claim 17, said one or more data types including records of paired wireless communication signals received from the power tool, said ideal state including— pre-defined states of the relay circuit that respectively correspond to time periods in which the paired wireless communication signals are received and in which the paired wireless communication signals are not received. 